The 20-year-old Southern Resident orca, who Balcomb says carried her calf more than 1,000 miles, captured national attention. The calf died a short time after it was born near Victoria, British Columbia on July 24, 2018 and J35 repeatedly saved its body from sinking according to a release from the Center for Whale Research.

Whale experts say they have seen orcas mourn their offspring before for up to a week, but J35 clung to her calf for an unusually long period of time.

Researchers had worried J35, who was last spotted with her dead calf Wednesday, was not eating properly and was spending too much energy pushing the corpse. However, there were never plans to intervene, and NOAA wildlife biologists said the idea of separating the pair was "not on the table."

Approximately 75% of newborns have not survived in the two decades since the designation of the Southern Resident killer whale population as “Endangered,” according to the Center for Whale Research. All of the pregnancies in the past three years have failed to produce viable offspring.

Meanwhile researchers have been tending to ailing orca J50, a 3½-year-old whale who has lost 20 percent of her body mass and developed a depression near the base of her skull. Crews injected J50 with antibiotics on Thursday.

Balcomb said he also saw J50 with her mother and brother on Saturday, along with NOAA researchers who were following her to collect prey remains and feces.